Physics Question 39 – JEE-MAIN 2026

The LED current $I_{LED}$ cannot exceed the total current $I_S$. This fact ($I_{LED}\le 0.5$ mA) combined with the power limit ($P_{LED}\le 2$ mW) directly implies an upper bound on the node voltage ($V_{node}\le 4$ V), which in turn provides a lower bound for $R_S$ ($R_S\ge 2$ kΩ).